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1.
Molecules ; 26(4)2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33669919

RESUMO

With the rapid development of global industry and increasingly frequent product circulation, the separation and detection of chiral drugs/pesticides are becoming increasingly important. The chiral nature of substances can result in harm to the human body, and the selective endocrine-disrupting effect of drug enantiomers is caused by differential enantiospecific binding to receptors. This review is devoted to the specific recognition and resolution of chiral molecules by chromatography and membrane-based enantioseparation techniques. Chromatographic enantiomer separations with chiral stationary phase (CSP)-based columns and membrane-based enantiomer filtration are detailed. In addition, the unique properties of these chiral resolution methods have been summarized for practical applications in the chemistry, environment, biology, medicine, and food industries. We further discussed the recognition mechanism in analytical enantioseparations and analyzed recent developments and future prospects of chromatographic and membrane-based enantioseparations.


Assuntos
Praguicidas/isolamento & purificação , Preparações Farmacêuticas/isolamento & purificação , Fracionamento Químico , Cromatografia , Praguicidas/química , Preparações Farmacêuticas/química , Estereoisomerismo
2.
Food Chem ; 352: 129187, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33652196

RESUMO

A novel covalent organic framework material (3DGA@COFs), for use as a solid-phase dispersion sorbent, has been synthesized for extracting organophosphorus pesticides (OPs) from vegetables. The prepared 3DGA@COFs material exhibited many advantageous features, including a large specific surface area (127.95 m2/g) and high pore volume (0.0344 cm3/g), which made it an ideal sorbent for sample pretreatment. The experimental conditions affecting extraction performance (adsorbent type, adsorbent amount, reaction time, pH, ionic concentration, and eluent) were optimized systematically. The extracted analytes were detected by HPLC-MS/MS. Under optimized conditions, the proposed method exhibited a wide linear range (0.5-100 µg/L) and low limits of detection (0.01-0.14 µg/L). The recoveries (75.40%-102.13%) satisfied the requirements for a precise detection method. The proposed method was successfully used for determining malathion, triazophos, quinalphos in lettuce, tomato and cucumber samples, thus indicating the potential of using 3DGA@COFs materials for pretreating vegetable samples.


Assuntos
Grafite/química , Hidrogéis/química , Estruturas Metalorgânicas/síntese química , Compostos Organofosforados/isolamento & purificação , Praguicidas/isolamento & purificação , Extração em Fase Sólida/métodos , Verduras/química , Adsorção , Técnicas de Química Sintética , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Estruturas Metalorgânicas/química , Compostos Organofosforados/análise , Compostos Organofosforados/química , Praguicidas/análise , Praguicidas/química , Fatores de Tempo
3.
Molecules ; 26(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668517

RESUMO

Insect plagues are a problem often hard to solve due to the harmful effects caused by the pesticides used to combat them. Consequently, the pesticide market is increasingly trying to develop new technologies to prevent the unwanted effects that common plague treatments usually bring with them. In this work, four specific bioattractants of Musca domestica, extracted from fungi (ß-ocimene, phenol, p-cresol, and indole) were microencapsulated with ß-cyclodextrin in order to produce an economically and environmentally sustainable bait containing biocides in the near future. Cyclodextrins will retain these volatile compounds until their use by the consumer when the product comes into contact with water. Then, the bioattractants will be released in the medium in a controlled manner. An analytical methodology based on headspace extraction coupled to gas chromatography and mass spectrometry (HS-GC/MS) has been developed and validated following Environmental Protection Agency (EPA) and European Commission Directorate General for Health and Food Safety guidelines for the bioattractants controlled release study from the microencapsulated product. The analytical method has been shown to be accurate and precise and has the sensitivity required for controlled release studies of the four bioattractants analyzed. The release of the bioattractants from microencapsulated products achieved the "plateau" after 3 h in all cases.


Assuntos
Composição de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/toxicidade , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Praguicidas/química , Reprodutibilidade dos Testes , Compostos Orgânicos Voláteis/análise , Água/química
4.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Praguicidas/farmacologia , Rosaceae/química , Bactérias/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Compostos Organotiofosforados/metabolismo , Compostos Organotiofosforados/farmacologia , Praguicidas/química , Praguicidas/metabolismo , Rosaceae/metabolismo , Tiametoxam/metabolismo , Tiametoxam/farmacologia
5.
Ecotoxicol Environ Saf ; 209: 111781, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340954

RESUMO

Compared with pristine agricultural polyethylene (PE) soil films microplastics (MPs), aged agricultural polyethylene (APE) soil films MPs have a rougher surface, more cracks and have some oxygen-containing functional groups that makes them adsorb organic pollutants, such as pesticides more easily. This may be more harmful to human beings than marine MPs as the agricultural soil films are closer to our living environment. But few works focused on the adsorption of pesticides on pristine or aged agricultural polyethylene soil films MPs. In order to promote the risk assessment of co-exposure of pesticides and agricultural polyethylene soil films MPs, a comparative study on the adsorption behavior and mechanism of four pesticides (carbendazim, diflubenzuron, malathion, difenoconazole) by pristine PE MPs and APE MPs were carried out in this paper. The results showed microcracks and surface oxidation observed on APE MPs. The adsorption kinetics and isotherm models indicated that the adsorption capacity of APE MPs was higher than that of PE MPs, which attribute to the larger surface area of APE MPs. The adsorption capacities of pesticides on APE MPs were positively correlated with LogKow (Water octanol partition coefficient) values of these four pesticides, showed the hydrophobic partitioning played the most important part in the adsorption, but also some H-bonding between secondary amines in the molecular of diflubenzuron and polar O-containing functional groups on APE MPs may be formed. And electrostatic forces or interactions are not the determining factor for these pesticides adsorption behavior of PE MPs, and the effect of pH is mainly driven by changes in sorbate properties rather than changes in surface properties of MPs. The results presented herein show the APE MPs can be a better vector of most hydrophobic pesticides than pristine MPs in the agricultural field, and more attention should be paid to the problem of films and pesticides residue in farmland soil.


Assuntos
Agricultura , Microplásticos/química , Praguicidas/química , Polietileno/química , Poluentes do Solo/química , Adsorção , Dioxolanos , Poluentes Ambientais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Plásticos/química , Solo/química , Triazóis , Água
6.
J Mater Chem B ; 9(3): 783-792, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33333547

RESUMO

Pesticides play a very important role in pest control and plant protection. However, they can be limited by a tendency to cause ecological system damage due to significant losses into the environment. To increase pesticide utilization efficiency, we developed highly leaf-adhesive avermectin nanocapsules (Av-pH-cat@CS) with pH-responsive controlled release properties. The Av-pH-cat@CS nanocapsules displayed good thermal stability and photostability in response to UV light irradiation. The Av-pH-cat@CS nanocapsules could be disrupted at low pH and they exhibited excellent controlled release in response to pH, which improved the release of avermectins. In addition, the Av-pH-cat@CS nanocapsules were highly adhesive to crop leaves as a result of strong hydrogen bonding, which prolonged the retention time on crop leaves. The Av-pH-cat@CS nanocapsules with pH-responsive release and strong leaf adhesion improved the control efficacy and enhanced the utilization efficiency. Our findings offer a promising approach to prolonging pesticide duration on crop leaves and improving the utilization efficiency.


Assuntos
Adesivos/química , Antiprotozoários/química , Ivermectina/análogos & derivados , Nanocápsulas/química , Praguicidas/química , Adesivos/síntese química , Antiprotozoários/síntese química , Liberação Controlada de Fármacos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Ivermectina/síntese química , Ivermectina/química , Estrutura Molecular , Tamanho da Partícula , Praguicidas/síntese química , Folhas de Planta/química , Propriedades de Superfície , Fatores de Tempo , Zea mays/química
7.
Ecotoxicol Environ Saf ; 203: 111046, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888614

RESUMO

Agricultural pesticides serve as effective controls of unwanted weeds and pests. However, these same chemicals can exert toxic effects in non-target organisms. To determine chemical modes of action, the toxicity ratio (TR) and critical body residues (CBRs) of 57 pesticides were calculated for Daphnia magna. Results showed that the CBR values of inert compounds were close to a constant while the CBR values of pesticides varied over a wider range. Although herbicides are categorized as specifically-acting compounds to plants, herbicides did not exhibit excess toxicity to Daphnia magna and were categorized as inert compounds with an average logTR = 0.41, which was less than a threshold of one. Conversely, fungicides and insecticides exhibited strong potential for toxic effects to Daphnia magna with an average logTR >2. Many of these chemicals act via disruption of the nervous, respiratory, or reproductive system, with high ligand-receptor binding activity which leads to higher toxicity for Daphnia magna. Molecular docking using acetylcholinesterase revealed that fungicides and insecticides bind more easily with the biological macromolecule when compared with inert compounds. Quantitative structure-activity relationship (QSAR) analysis revealed that the toxicity of fungicides was mainly dependent upon the heat of formation and polar surface area, while the toxicity of insecticides was more related to hydrogen-bond properties. This comprehensive analysis reveals that there are specific differences in toxic mechanisms between fungicides and insecticides. These results are useful for determining relative risk associated with pesticide exposure to aquatic crustaceans, such as Daphnia magna.


Assuntos
Daphnia/efeitos dos fármacos , Modelos Biológicos , Praguicidas/química , Praguicidas/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Ligação de Hidrogênio , Inseticidas/química , Inseticidas/toxicidade , Simulação de Acoplamento Molecular , Resíduos de Praguicidas/metabolismo , Relação Quantitativa Estrutura-Atividade
8.
PLoS One ; 15(9): e0239298, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986745

RESUMO

The increasing number of fraudulent pesticides on the market not only constitutes a major threat to sustainable agriculture but can also have adverse consequences for the environment and human health. The purpose of this study is to assess farmers' risk perception with regard to fraudulent pesticides and to establish the determinants of their perception. Data were collected through structured questionnaires from 370 farmers from the eastern region in Saudi Arabia. The findings showed that farmers had a high perception of physical, legal, social, and physiological risks of counterfeit pesticides, while they had a moderate perception of agri-environmental risks (M = 3.47, SD = 0.72) and economic risks (M = 3.52, SD = 1.11). Moreover, 73.5% of farmers reported that they had purchased fraudulent pesticides in the last three years. The results of the t-test revealed that the number of farmers who had purchased fraudulent pesticides was significantly higher than the number of farmers who had not purchased such pesticides regarding the perception of the majority of risks, except for physical risk. Multivariate regression analyses showed that age, farm size, farming experience, extension contact, and purchased fraudulent pesticides were significantly associated with risk perception. The findings suggest that awareness campaigns on recognizing fraudulent pesticides among farmers are needed, as well as policy measures, to combat counterfeiting in the agricultural sector in cooperation with other stakeholders.


Assuntos
Fazendeiros , Conhecimentos, Atitudes e Prática em Saúde , Exposição Ocupacional/normas , Praguicidas/química , Idoso , Agricultura , Humanos , Masculino , Pessoa de Meia-Idade , Praguicidas/toxicidade , Arábia Saudita/epidemiologia , Inquéritos e Questionários
9.
J Chromatogr A ; 1628: 461447, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822986

RESUMO

Waterfowl populations have been decreasing in Europe for the last years and pollution appears to be one of the main factors. This study was conducted to develop a single sensitive and robust analytical method for the monitoring of 2 fungicides, 15 herbicides, 3 insecticides and 24 transformation products in wild bird eggs. One of the major challenges addressed was the characterization of chemicals with large logP range (from -1.9 to 4.8). A total of 11 different extraction parameters were tested in triplicate to optimize the extraction protocol, on generic parameters, buffer addition and use of clean-up steps. Quantification was based on matrix-match approach with hen eggs as reference matrix (34 analytes with r²>0.99). Particular attention was payed to matrix effects (-28% on average), quantification limits (0.5 to 25 ng.g-1 dry mass / 0.2 to 7.5 ng.g-1 fresh mass) and extraction yields (46 to 87% with 25 analytes up to 70%) to ensure the relevance of the method and its compatibility with ultra-trace analysis. It led to a simple solid/liquid low temperature partitioning extraction method followed by LC-MS/MS. Analysis of 29 field samples from 3 waterfowl species revealed that eggs were slightly contaminated with pesticides as only one egg presented a contamination (terbutryn, herbicide, 0.7 ng.g-1) and confirmed the relevance of the method.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida , Ovos/análise , Praguicidas/análise , Espectrometria de Massas em Tandem , Animais , Aves , Poluentes Ambientais/análise , Europa (Continente) , Praguicidas/química
10.
Chemosphere ; 261: 127762, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32738715

RESUMO

The presence of microplastics (MPs) and their effects have been widely investigated in the aquatic environment, whereas the research done in the terrestrial environment is incomparably lacking. MPs are considered a pollutant in soil on agricultural land, where they can act as a vector for other pollutants, namely organic chemical compounds, such as pesticides. In soil, presence of MPs is affecting the growth and life of microorganisms in it. The interactions between two types of MPs and three pesticides in the mixture with alluvial soil were studied. Adsorption of acetamiprid, chlorantraniliprole and flubendiamide in concentrations of 1, 5 and 10 mg L-1 onto polyester fibres and polypropylene particles of 0.5-1 mm size was studied at 1% and 5% (w/w) of their content in soil. Results showed that the adsorption of pesticides was dependent on their octanol/water partition coefficient, with the most highly adsorbed pesticide also being the most hydrophobic, regardless of the type and form of MPs. Adsorption of pesticides onto MP particles was confirmed in soil-MPs mixtures with 5% polypropylene and 5% polyester at all tested pesticides' concentrations, proving that MPs in soil systems act as carriers to pollutants. MPs in soil decreased the soil's intrinsic capacity to retain pesticides, indicating the possibility of a greater mobility of pesticides on MPs through the soil system.


Assuntos
Benzamidas/química , Microplásticos/química , Neonicotinoides/química , Poluentes do Solo/química , Sulfonas/química , ortoaminobenzoatos/química , Adsorção , Agricultura , Poluentes Ambientais , Praguicidas/química , Plásticos , Solo , Poluentes do Solo/análise
11.
Aquat Toxicol ; 227: 105589, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32841884

RESUMO

Pesticides have an impact on the aquatic environment, with ecological effects. The regulation of this impact is of key importance. One of the components of the planning of agricultural and industrial activities is the development of databases and models in order to identify substances that may cause damage. In this study, a quantitative structure-activity relationship (QSAR) approach was established for the prediction of acute toxicity toward rainbow trout of various pesticides. The so-called index of ideality of correlation is the main component of this approach. The validation of this approach has been carried out with three random splits into the training and validation sets. The range of statistical quality of models obtained here for the validation set is R2 = [0.81-0.86] and RMSE = [0.55-0.65].


Assuntos
Modelos Teóricos , Oncorhynchus mykiss , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bases de Dados Factuais , Método de Monte Carlo , Praguicidas/química , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/química
12.
Chemosphere ; 261: 127637, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32717508

RESUMO

Conazole fungicides are currently used pesticides with considerable chronic toxicity and ecotoxicity that are also on EU list for substitution. They enter the soil forming short- or long-term residues. In this study two of their representatives, epoxiconazole (EPC) and tebuconazole (TBC), have been tested with 20 soils from the Czech Republic for their adsorption. Adsorption, by means of Kd coefficients, was compared to "basic" (TOC, pH, clay …) and "advanced" (surface area, minerals ..) soil properties. After doing multivariate analysis of the variables it was apparent that adsorption of both pesticides was highly associated with pH (negatively correlated), and less associated with soil organo-mineral complex (TOC, clay and surface area) and C and N in soil organic matter (OM). Particle sizes or cation exchange capacity (CEC) did not show correlation with adsorption, but showed an association in multidimensional space in factor analysis (FA). Some correlations were revealed between EPC adsorption and soil organic matter parameters. Recalculating Kd to Koc and to Gibb's free energy (ΔG) and its values indicated that the adsorption of EPC and TBC is mainly weak physical adsorption - partitioning. Also, ΔG values gave better correlation with pH(H2O) than Kd. Surface area impacted EPC adsorption. From the several soil minerals, kaolinite showed EPC and TBC adsorption. EPC adsorption was not highly influenced with pH changes compared to TBC. The number and types of H-bonds with molecular geometry govern the sorption, which might crucially affect leachibility in soil, and this may indicate that TBC is more leachable than EPC for the same soil.


Assuntos
Compostos de Epóxi/química , Poluentes do Solo/química , Triazóis/química , Adsorção , Agricultura , Cátions , Argila , República Tcheca , Minerais/química , Tamanho da Partícula , Praguicidas/química , Solo/química
13.
PLoS One ; 15(7): e0235345, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667930

RESUMO

This study was carried out to investigate the risks of simultaneous exposure to pesticide residues and bacteria contaminants in locally produced fresh vegetables and vegetables in Tanzania. A total of 613 samples were analyzed for pesticide residues, out of which 250 were also analyzed for bacterial contamination. Overall, 47.5% had pesticide residues, 74.2% exceeded Maximum Residue Levels (MRLs). Organophosphorus (95.2%), organochlorines (24.0%), pyrethroids (17.3%), and carbamates (9.2%) residues dominated. MRL values were mostly exceeded in tomatoes, onions, watermelons, cucumbers, Chinese cabbage, and sweet paper. Tetramethrin (0.0329-1.3733 mg/kg), pirimiphos-methyl (0.0003-1.4093 mg/kg), permethrin (0.0009-2.4537 mg/kg), endosulfan (beta) (0.0008-2.3416 mg/kg), carbaryl (0.0215-1.5068 mg/kg), profenofos (0.0176-2.1377 mg/kg), chlorpyrifos (0.0004-1.2549 mg/kg) and dieldrin (0.0011-0.5271 mg/kg) exceeded MRLs. The prevalence of bacteria contamination was high (63.2%). Enterobacter (55.6%) Pseudomonas aeruginosa (32.4%), E. coli (28.2%), Citrobacter (26.8%), Klebsiella oxytoca (14.8%), and Salmonella (7.7%) were isolated. Furthermore, 46.4% tested positive for both pesticide residues and bacterial contaminants. Vegetables from farms (60.7%) contained more dual contaminants than market-based vegetables (41.8%). This may have resulted from excessive pesticide use and unhygienic handling of fresh fruits and vegetables at production level. Binary logistic regression showed that fresh fruits and vegetables with pesticide residues were 2.231 times more likely to have bacteria contaminants (OR: 2.231; 95% CI: 0.501, 8.802). The contamination levels of pesticide residues and bacterial contaminants could be perceived as a serious problem as most fresh fruits and vegetables recorded values of pesticide residues far above the MRLs with pathogenic bacteria isolated in higher proportions. MRLs was higher in most vegetables consumed raw or semi-cooked such as watermelons, carrots, cucumber, tomatoes, onion and sweet paper. There is an urgent need to develop pesticide monitoring and surveillance systems at farmer level, educating farmers and promoting the use of greener pesticides to mitigate the health effects of pesticides and bacterial contaminants.


Assuntos
Contaminação de Alimentos/análise , Frutas/efeitos adversos , Praguicidas/efeitos adversos , Verduras/efeitos adversos , Citrobacter/isolamento & purificação , Citrobacter/patogenicidade , Enterobacter/isolamento & purificação , Enterobacter/patogenicidade , Frutas/química , Frutas/microbiologia , Humanos , Hidrocarbonetos Clorados/efeitos adversos , Hidrocarbonetos Clorados/química , Klebsiella oxytoca/isolamento & purificação , Klebsiella oxytoca/patogenicidade , Resíduos de Praguicidas/efeitos adversos , Resíduos de Praguicidas/química , Praguicidas/química , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/patogenicidade , Piretrinas/efeitos adversos , Piretrinas/química , Salmonella/isolamento & purificação , Salmonella/patogenicidade , Verduras/química , Verduras/microbiologia
14.
J Chromatogr A ; 1625: 461340, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709363

RESUMO

In this study, a magnetized polyethylene composite has been prepared using ball milling procedure and employed as an efficient sorbent in magnetic dispersive solid phase extraction combined with dispersive liquid-liquid microextraction. This method has been utilized for the extraction and preconcentration of some pesticides from fruit juices prior to their quantification by gas chromatography-flame ionization detection. The prepared sorbent consisted of the natural iron oxide (obtained from sand) coated with polyethylene. In the present work, first a few mg of the magnetic composite is added into an aqueous solution containing the analytes and vortexed. After that the analytes are eluted with iso-propanol from the surface of the composite particles separated in the presence of a strong external magnetic field. For further enrichment of the analytes, 1,2-dibromoethane (at µL-level) as an extraction solvent is mixed with the obtained eluent and hastily injected into deionized water. The composite was characterized using techniques including vibrating sample magnetometry, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Brunauer-Emmett-Teller nitrogen sorption, and Fourier transform infrared spectrophotometry. Under optimal conditions, the method provided low limits of detection (0.94-1.9 µg L-1) and quantification (3.2-5.9 µg L-1), high enrichment factors (570-692), good linearity (r2 ≥ 0.994), and satisfactory repeatabilities (relative standard deviations ≤ 8% for intra- and inter-day precisions at a concentration of 15 µg L-1 of each analyte).


Assuntos
Fenômenos Magnéticos , Praguicidas/isolamento & purificação , Polietileno/química , Polietileno/síntese química , Adsorção , Centrifugação , Cromatografia Gasosa , Sucos de Frutas e Vegetais/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Microextração em Fase Líquida , Concentração Osmolar , Praguicidas/análise , Praguicidas/química , Reprodutibilidade dos Testes , Extração em Fase Sólida , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Difração de Raios X
15.
Ecotoxicol Environ Saf ; 201: 110812, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32512419

RESUMO

Pesticides are widely used chemical compounds in agriculture to destroy insects, pests and weeds. In modern era, they form an indispensable part of agricultural and health practices. Globally, nearly 3 billion kg of pesticides are used every year with a budget of ~40 billion USD. This extensive usage has increased the crop yield as well as led to significant reduction in harvest losses and thereby, enhanced food availability. On the other hand, indiscriminate usage of these chemicals has led to several environmental implications and caused adverse effects on human health. Epidemiological evidences have revealed the harmful effects of pesticides exposure on various organs including liver, brain, lungs and colon. Recent investigations have shown that pesticides can also lead to fatal consequences such as cancer among individuals. These chemicals enter ecosystem, thus hampering the sensitive environmental equilibrium through bio-accumulation. Due to their non-biodegradable nature, they can persist in nature for years and are regarded as potent biohazard. Worldwide, very few surveillance methods have been considered, which can bring awareness among the individuals, therefore the present review is an attempt to delineate consequences induced by various types of pesticide exposure on the environment. Further, the prospective of biopesticides use could facilitate the increase of crop production without compromising human health.


Assuntos
Agentes de Controle Biológico/toxicidade , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Praguicidas/toxicidade , Agentes de Controle Biológico/química , Produção Agrícola/métodos , Ecossistema , Exposição Ambiental/análise , Poluentes Ambientais/química , Humanos , Praguicidas/química
16.
J Chromatogr A ; 1624: 461240, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540078

RESUMO

In this work, the use of different solvents and temperatures was explored, aiming to evaluate their influence on the enantioseparation of pesticides by HPLC in polar-organic conditions, employing a column containing immobilized amylose tris(3-chloro-5-methylphenyl-carbamate). The chiral separation of seventeen different pesticides widely used as herbicides, fungicides, insecticides and precursors were studied. The mobile phases included methanol, ethanol, iso-propanol, n-propanol and acetonitrile; either pure or containing additives such as diethylamine, trifluoroacetic acid, formic acid, acetic acid or mixtures thereof. We studied the influence of these eluents on chiral separation of those pesticides in terms of retention factor, enantioselectivity, enantioresolution and peak symmetry. Regarding temperature influence, evaluated within the range 5 - 40 °C, nearly all the compounds decreased their retention and selectivity factors with the increase in temperature, although the effect was dependent on the mobile phase solvent. Moreover, estimation of thermodynamic parameters was performed based on linear van´t Hoff plots.


Assuntos
Amilose/análogos & derivados , Compostos Orgânicos/química , Praguicidas/química , Praguicidas/isolamento & purificação , Fenilcarbamatos/química , Temperatura , Amilose/química , Cromatografia Líquida de Alta Pressão , Padrões de Referência , Solventes/química , Estereoisomerismo
17.
Chemosphere ; 258: 127217, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32535437

RESUMO

The widespread use of pesticides has received increasing attention in regulatory agencies because their extensive overuse and various adverse effects on all living organisms. Organizations such as EPA and ECHA have published laws that pesticides should be fully evaluated before bring them to market. In the present study, we evaluated the pesticides toxicity using the Quantitative Structural-Activity Relationship (QSAR) method. The models for the single class pesticides (herbicides, insecticides and fungicides) as well as the general class pesticides (the combined dataset plus some microbicides, molluscicides, etc.) were developed using the Genetic Algorithm and Multiple Linear Regression method. The internal and external validation results suggested that all the obtained models were stable and predictive. According to the modeling descriptors, the lipophilic descriptors contributed positively while all the electrotopological state descriptors showed a negative contribution, their presences in every model verified the conspicuous influence of molecular lipophilicity and hydrophilicity on the pesticides toxicity. However, the influence of topological structure descriptors was different and varies with the physiochemical information they encode. Finally, the models presented in this paper would help assess the pesticides toxicity against Americamysis bahia, shorten test time, and reduce the cost of pesticides risk assessment.


Assuntos
Crustáceos/efeitos dos fármacos , Modelos Teóricos , Praguicidas/química , Praguicidas/toxicidade , Animais , Bases de Dados Factuais , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Inseticidas/química , Inseticidas/toxicidade , Modelos Lineares , Relação Quantitativa Estrutura-Atividade
18.
Ecotoxicol Environ Saf ; 199: 110679, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32402896

RESUMO

Chlordane is a worldwide banned organochlorine insecticide because of its hazard to animal and human health. It is also a persistent organic pollutant, which can affect either the soil or the aquatic life. The same applies to other chlorinated cyclodiene insecticides, such as dieldrin and aldrin. In turn, organofluorine compounds have a widespread use in agriculture. Therefore, density functional calculations and docking studies showed that the bioisosteric replacement of chlorines in the above-mentioned compounds by fluorines improves some physicochemical parameters used to estimate the toxicity and environmental risk of these compounds, as well as the ligand-enzyme (GABAA receptor-chloride channel complex) interactions related to their insecticidal activity. This work is an effort to provide an improved new class of organofluorine pesticides.


Assuntos
Hidrocarbonetos Clorados/química , Hidrocarbonetos Fluorados/química , Modelos Teóricos , Praguicidas/química , Receptores de GABA-A/química , Animais , Fenômenos Químicos , Halogenação , Humanos , Hidrocarbonetos Clorados/farmacologia , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Fluorados/farmacologia , Hidrocarbonetos Fluorados/toxicidade , Simulação de Acoplamento Molecular , Praguicidas/farmacologia , Praguicidas/toxicidade
19.
Toxicol Lett ; 329: 1-11, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32371136

RESUMO

In spring 2016, a study was carried out to characterize currently used pesticide (CUP) exposure among children living in Wallonia (Belgium). Pesticides were measured in both first morning urine voids of 258 children aged from 9 to 12 years and in ambient air collected close to the children's schools. Out of the 46 pesticides measured in the air, 19 were detected with frequencies varying between 11 % and 100 %, and mean levels ranging from <0.04 to 2.37 ng/m³. Only 3 parent pesticides were found in 1-10% of the urine samples, while all the metabolites analyzed were positively detected at least once. The captan metabolite (THPI) was quantified in 23.5 % of the samples, while 3,5,6-trichloro-2-pyridinol (chlopryrifos metabolite) was detected in all urines with levels ranging from 0.36-38.96 µg/l. 3-phenoxybenzoic acid (3-PBA), trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (t-DCCA) and diethylphosphate were the most abundant pyrethroid metabolites and dialkylphosphate measured. The air inhalation was demonstrated to be a minor route of exposure for the selected CUPs. Statistical regressions highlighted predictors of exposure for some pesticides such like consumption of grey bread, presence of carpets at home or indoor use of pesticides, although no clear source was identified for most of them.


Assuntos
Poluentes Atmosféricos/urina , Exposição Ambiental , Praguicidas/urina , Poluentes Atmosféricos/química , Bélgica , Criança , Monitoramento Ambiental , Feminino , Humanos , Masculino , Praguicidas/química
20.
Chemosphere ; 256: 127139, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470737

RESUMO

The existence of ß-naphthoxyacetic acid (BNOA) pesticide in water system has aroused serious environmental problem because of its potential toxicity for humans and organisms. Therefore, exploiting an efficient method without secondary pollution is extremely urgent. Herein, a promising Ti/PbO2-Co-Pr composite electrode has been successfully fabricated through simple one-step electrodeposition for efficiently electrocatalytic degradation of BNOA. Compared with Ti/PbO2, Ti/PbO2-Co and Ti/PbO2-Pr electrodes, Ti/PbO2-Co-Pr electrode with smaller pyramidal particles possesses higher oxygen evolution potential, excellent electrochemical stability and outstanding electrocatalytic activity. The optimal degradation condition is assessed by major parameters including temperature, initial pH, current density and Na2SO4 concentration. The degradation efficiency and chemical oxygen demand removal efficiency of BNOA reach up to 94.6% and 84.6%, respectively, under optimal condition (temperature 35 °C, initial pH 5, current density 12 mA cm-2, Na2SO4 concentration 8.0 g L-1 and electrolysis time 3 h). Furthermore, Ti/PbO2-Co-Pr electrode presents economic energy consumption and superior repeatability. Finally, the possible degradation mechanism of BNOA is put forward according to the main intermediate products identified by liquid chromatography-mass spectrometer. The present research paves a new path to degrade BNOA pesticide wastewater with Ti/PbO2-Co-Pr electrode.


Assuntos
Eletrólise/métodos , Glicolatos/química , Chumbo/química , Praguicidas/química , Titânio/química , Águas Residuárias/análise , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Eletrodos , Eletrólise/instrumentação , Galvanoplastia , Oxirredução , Óxidos/química , Sulfatos/química
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